diff --git a/Dockerfile b/Dockerfile
index 9d404ef..ba432a9 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -8,6 +8,7 @@ RUN apt-get update --fix-missing && \
     lua-sec \
     lua-unbound \
     openssl \
+    ca-certificates \
     netcat-traditional \
     && rm -rf /var/lib/apt/lists/*